Technical Field
The present invention relates to bearing devices used in machine tools, industrial machinery, etc., and particularly to a bearing device constituted as a combination of a bearing and an oil supply unit.
Background Art
A bearing device which incorporates an oil supply unit therein is conventional (see Patent Literature 1). This bearing device is a rolling bearing and an oil supply unit is mounted on an inner diameter surface of one of two mutually opposed track rings, or a fixed-side track ring in this case. The oil supply unit includes a tank which stores lubrication oil; a pump which pumps out the lubrication oil stored in the tank into the bearing; and an electric generator which drives the pump. The device also includes means which controls the pump based on bearing conditions thereby controlling an amount of discharged oil. Patent Literature 2 shows another bearing device which includes a similar oil supply unit.
Patent Literature 3 shows a rolling bearing device, in which a lubrication oil tank of the oil supply unit is detachable/attachable and is mounted between a fixed-side track ring and a rotation-side track ring. The oil supply unit has a casing which serves as the lubrication oil tank.
All of these conventional examples described above have a shared arrangement that the lubricant is supplied to the bearing by a pump which is a constituent component of the oil supply unit.